Explosion at horse center kills worker, horse

OCALA, Fla. - An apparent spark within the high-oxygen chamber of a Florida equine sports medicine center triggered a massive explosion Friday that caused part of the building to collapse, killing a worker and a horse, authorities said.

Erica Marshall, 28, died in explosion at the Kesmarc Farm and Equine Rehabilitation Center in Ocala, the Marion County Sheriff's Office said. A second worker, Sorcha Moneley, was airlifted to Shands at the University of Florida in Gainesville with serious injuries.

The explosion happened at a large building that contained stables. The blast involved a hyperbaric aquatic chamber, a cylindrical machine about 12 feet in diameter that uses compressed oxygen to help rehabilitate horses.

County fire officials said it was not immediately clear what caused the spark. The Florida State Fire Marshal's Office is investigating the cause of the explosion.

The explosion didn't cause a fire but partially collapsed the building's southwest corner, where the hyperbaric aquatic chamber was located, fire officials said.

About 30 other horses kept in the building were not injured. Their owners were contacted, and the animals were moved.

The center opened in 2009 to aid in the recovery and conditioning of horses. A telephone message left for the facility wasn't immediately returned on Friday.